Gorbachev Supports Zone Free Of Chemical Weapons

MOSCOW — Soviet leader Mikhail Gorbachev said Tuesday that the Soviet Union would back establishment of a zone free of chemical weapons in Europe if the United States supported the proposal.

In a meeting with Johannes Rau, vice chairman of West Germany's center- left opposition Social Democratic Party and the party's likely next candidate for chancellor, Gorbachev said that if such a zone were created the Soviet Union would ''guarantee and respect'' it, the Soviet news agency Tass said.

A White House spokesman later rejected the idea. Spokesman Edward Djerejian said the United States seeks ''a comprehensive, verifiable ban'' on chemical weapons, and ''until such a ban is negotiated, the U.S. must maintain a credible deterrent against Soviet use of chemical weapons.''

A White House official who asked not to be identified said the United States has no plans to place chemical weapons in foreign countries.

Gorbachev's expression of support for such a zone during his meeting with Rau is viewed here as part of a tendency by the Kremlin to support causes popular with the Western European Social Democratic parties. The campaign, diplomats said, is likely to intensify as the November summit meeting between Gorbachev and President Reagan nears.

President Reagan warned Tuesday against ''wishful thinking or public- relations campaigns'' in advance of the November summit. He said he intends to remind Gorbachev of ''why we believe they represent a threat to us and to the Western world.''

Reagan said he hopes the Geneva meeting with Gorbachev will demonstrate to the Soviets ''by deed, not word, that we are not an aggressor.''